Scroll compressor

ABSTRACT

A scroll compressor which is capable of preventing thermal damage to an O-ring and has a filter arrangement structure with favorable installation work efficiency is provided. The compressor is configured such that an intake pipe ( 50 ) for drawing in a refrigerant gas through an external pipe (P) is securely joined to a steel compressor casing ( 10 ) by penetrating therethrough, the compressor casing housing a stationary scroll ( 22 ) and a swingable scroll ( 24 ); and the lower end part of the intake pipe is fitted into an intake portion ( 22 K) with an O-ring ( 60 ) disposed therebetween, the intake portion being provided in the stationary scroll. The intake pipe is configured to have a steel iron pipe body ( 54 ) on the intake portion side and a copper pipe body ( 52 ) joined to the upper end part of the iron pipe body. The copper pipe body of the intake pipe is silver-brazed ( 13 ) to the compressor casing, and a filter (F) is installed in the intake pipe.

TECHNICAL FIELD

The present invention relates to a scroll type compressor which is provided in an intake pipe with a filter for removing dust mixed possibly in a refrigerant gas flowing through a refrigerant, gas pipe, the intake pipe being connected to the refrigerant gas pipe from an evaporator in a refrigeration cycle so as to draw in the refrigerant gas.

BACKGROUND ART

Scroll type compressors are available as a compressor for drawing in and compressing a refrigerant gas flowing through a refrigerant gas pipe from an evaporator in a refrigeration cycle. As this scroll type compressor, disclosed in Patent Literature 1 listed below is a structure in which an intake pipe 51 made of an integrated material is joined to an end cap 4A which is a part of a compressor casing. Furthermore, the top part of the intake pipe 51 is fitted into an inlet 18 of a stationary scroll 12 with an O-ring disposed therebetween for preventing leakage of the refrigerant gas. Note that the integrated material is typically considered to be steel. Furthermore, disclosed in Patent Literature 2 is an air filter for scroll-type fluid machinery.

PRIOR ART DOCUMENT Patent Literature

Patent Literature 1: Japanese Patent Application Laid-Open No. 2009-228439

Patent Literature 2: Japanese Patent Application Laid-Open No. 2008-267142

SUMMARY OF INVENTION Problems to be Solved by Invention

However, when the intake pipe is made of steel as disclosed. in Patent Literature 1 and is welded to the end cap made of steel, welding heat may cause thermal damage to the O-ring. Furthermore, in the refrigeration cycle, as disclosed in Patent. Literature 2 above, it is necessary to install a filler somewhere in the refrigerant, piping circuit in order to remove dust in the refrigerant gas. It would be preferable to be capable of placing this filter by efficient work.

It is therefore an object of the invention to solve the problem by providing a scroll compressor which is capable of preventing thermal. damage to an O-ring and which has a filter arrangement structure with favorable installation work efficiency.

Means for Solving Problems

In view of the aforementioned problem, the first invention provides a scroll compressor in which an intake pipe for drawing in a refrigerant gas through an external pipe is securely joined to a steel compressor casing by penetrating therethrough, the compressor casing being configured to house a stationary scroll and a swingable scroll; and the lower end part of the intake pipe is fitted into an intake portion with an O-ring disposed therebetween, the intake portion being provided in the stationary scroll. The scroll compressor is characterized in that the intake pipe is configured to have a steel iron pipe body on the intake portion side and a copper pipe body joined to the upper end part of the iron pipe body, the copper pipe body being made of copper or another metal the surface of which is plated with copper; the copper pipe body of the intake pipe is silver-brazed to the compressor casing; and a filter for removing dust mixed in the refrigerant gas is installed in the intake pipe.

The second invention, an aspect of the first invention, provides a scroll compressor An which an intake pipe for drawing in a refrigerant gas through an external pipe is securely joined to a steel compressor casing by penetrating therethrough, the compressor casing being configured to house a stationary scroll and a swingable scroll; and the lower end part of the intake pipe is fitted into an intake portion with an O-ring disposed. therebetween, the intake portion being provided in the stationary scroll. The scroll compressor is characterized in that the intake pipe is configured to have a steel iron pipe body on the intake portion side and a copper pipe body joined to the upper end part of the iron pipe body, the copper pipe body being made of copper or another metal the surface of which is plated. with copper; the copper pipe body of the intake pipe is silver-brazed to the compressor easing; a stepped portion which has an inner diameter equal to or less than the minimum inner diameter of the copper pipe body and which is opened toward the copper pipe body is provided inside the iron pipe body; and the opening edge portion of a filter for removing dust mixed in the refrigerant gas has an outer diameter which allows for passing through a region of the minimum inner diameter, with the opening edge portion of the filter press-fitted into the stepped portion.

The third invention is configured such that the filter of the first or second invention is formed by soldering.

A fourth invention is configured such that the filter of the first or second invention is a mesh of thin metal wire, and the opening edge portion is formed by securely caulking a region into which the opening edge portion of the body of the filter is outwardly turned over.

The fifth invention, an aspect of the first invention, provides a scroll compressor in which an intake pipe for drawing in a refrigerant gas through an external pipe is securely joined to a steel compressor casing by penetrating therethrough, the compressor casing being configured to house a stationary scroll and a swingable scroll; and the lower end part of the intake pipe is fitted into an intake portion with an O-ring disposed therebetween, the intake portion being provided in the stationary scroll. The scroll compressor is characterized in that the intake pipe is configured to have a steel iron pipe body on the intake portion side and a copper pipe body joined to the upper end part of the iron pipe body, the copper pipe body being made of copper or another metal the surface of which is plated with copper; the copper pipe body of the intake pipe is silver-brazed to the compressor casing; and the opening edge portion of a filter for removing dust mixed in the refrigerant gas is sandwiched between the iron pipe body and the copper pipe body in a joint area thereof.

EFFECTS OF INVENTION

In the first invention, the intake pipe is configured to have an iron pipe body as the lower side and a copper pipe body as the upper side, with the copper pipe body silver-brazed to the steel compressor casing. Thus, heat generated during the silver brazing can be made lower in temperature than heat produced during welding. It is thus possible to prevent thermal damage to the O-ring even during fabrication/manufacture with the O-ring pre-mounted on the intake pipe. Furthermore, since the intake pipe is formed of two parts, i.e., the iron pipe body and the copper pipe body, it is possible to install the filter in the intake pipe as a passing work when these two parts are joined together to form the intake pipe. That is, the filter can be installed with favorable work efficiency.

In the second invention, the intake pipe is configured to have an iron pipe body as the lower side and a copper pipe body as the upper side, with the copper pipe body silver-brazed to the steel compressor casing. Thus, heat generated during the silver brazing can be made lower in temperature than heat produced during welding. It is thus possible to prevent thermal damage to the O-ring even during fabrication/manufacture with the O-ring pre-mounted on the intake pipe. Furthermore, since the intake pipe is formed of two parts, i.e., the iron pipe body and the copper pipe body, it is possible to provide a stepped portion inside the iron pipe body when the intake pipe is in the form of parts. Since the inner diameter of the stepped portion is equal to or less than the minimum inner diameter of the copper pipe body, the iron pipe body and the copper pipe body can he joined together and thereafter, the filter can be inserted from the copper pipe body side (from above) so as to press fit the opening edge portion into the stepped portion. Thus, forming the intake pipe of the two parts makes it possible to facilitate installation of the filter as a passing work, i.e., with favorable installation work efficiency.

In the third invention, the filter is formed by soldering. The filter can be press fitted after the iron pipe body and the copper pipe body are joined together as well as the copper pipe body of the intake pipe is silver-brazed to the compressor casing. It is thus possible to prevent the filter from being subjected to heat produced during joining each portion together. This also prevents the solder from being melted and thermal damage to the filter.

In the fourth invention, the filter is a mesh of thin metal wire. The filter can be press fitted. after the iron pipe body and the copper pipe body are joined together as well as the copper pipe body of the intake pipe is silver-brazed to the compressor casing. It is thus possible to prevent the filter from being subjected to heat produced during joining each portion together. This also prevents thermal damage to the thin metal wire, that is, the filter.

In the fifth invention, the intake pipe is configured to have an iron pipe body as the lower side and a copper pipe body as the upper side, with the copper pipe body silver-brazed to the steel compressor casing. Thus, heat generated during the silver brazing can be made lower in temperature than heat produced during welding. It is thus possible to prevent thermal damage to the O-ring even during fabrication/manufacture with the O-ring pre-mounted on the intake pipe. Furthermore, since the. intake pipe is formed of two parts, i.e., the iron pipe body and the copper pipe body, the opening edge portion of the filter can be sandwiched between the iron pipe body and the copper pipe body in the joint area thereof by a passing work when these two parts are joined together to form the intake pipe. Thus, the filter can be installed with favorable installation work efficiency.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a longitudinal sectional view illustrating a scroll compressor according to the present invention.

FIG. 2 is an enlarged view illustrating a main portion of the scroll compressor of FIG. 1.

FIG. 3 is a further enlarged longitudinal sectional view illustrating the main portion of FIG. 2.

FIG. 4 is a longitudinal sectional view illustrating a modified embodiment of FIG. 3.

DESCRIPTION OF EMBODIMENTS

Now, the present invention will be described in more detail with reference to the accompanying drawings. First, reference will be made to FIG. 1. Scroll type compressors are connected to a refrigerant gas pipe P from an evaporator in a refrigerant circuit (not shown) through which a refrigerant circulates to perform a refrigeration cycle operation, and are configured to compress a refrigerant gas. This compressor has a compressor casing 10 which is of a hermetically sealed dome type with a vertically elongated cylindrical shape. The compressor casing 10, which is constructed as a pressure vessel, is made up of a casing body 12 being a cylindrical barrel section that has an axial line extending in the vertical direction; an upper end cap 14 which is integrally welded thereto so as to hermetically seal the upper end thereof and which is bowl-shaped to be protruded upwardly; and a lower end cap (bottom) 16 which is integrally welded to the casing body 12 so as to hermetically seal the lower end thereof and which is bowl-shaped to be protruded downwardly.

Housed inside the compressor casing 10 are a scroll type compression mechanism 20 for compressing the refrigerant gas; and a driving motor 30 which is disposed below the scroll type compression mechanism 20. The scroll type compression mechanism 20 and the driving motor 30 are coupled to each other by means of a driving shaft 36 which extends in the vertical direction within the compressor casing 10 and serves as the output shaft of the driving motor 30. There is also formed a high-pressure space KK between the scroll type compression mechanism 20 and the driving motor 30.

The scroll type compression mechanism 20 includes an annular main frame 40; a stationary scroll 22 disposed in close contact with the upper surface of the main frame 40; and a swingable scroll 24 disposed between the stationary scroll 22 and the main frame 40 so as to be swingingly engaged with the stationary scroll 22. The main frame 40 is secured, on the entire outer peripheral surface thereof, to the casing body 12. Furthermore, the main frame 40 divides inside the compressor casing 10 into the high-pressure space KK below the main frame 40 and a discharge space TK above the main frame 40. The spaces KK and TK are in communication with each other via a vertical groove N which is formed to vertically extend through each of the circumferential portions of the main frame 40 and the stationary scroll 22. The refrigerant gas compressed with the scroll type compressor 20 to a high pressure flows sequentially through the discharge space TK, the vertical groove N, and the high-pressure space KK.

The main frame 40 has, at the center of the lower surface, a bearing unit 40T which bears the driving shaft 36 rotatably on a radial bearing 39 and is protruded downwardly. Furthermore, the driving shaft 36 is integrally provided, on the upper end, with an eccentric shaft portion 38 which has a center axis line that is decentered from the center axis line of the driving shaft 36. The eccentric shaft portion 38 is inserted into a cylindrical. boss portion 24B, which is protruded downwardly at the center of the lower, surface of an end plate 24A of the swingable scroll 24, allowing the eccentric shaft portion 38 and the boss portion 24B to be relatively rotatable. The main frame 40 is provided with a space 40H which is formed above and in communication with the hole of the bearing unit 40T, the space 40H allowing the boss portion 24B of the swingable scroll 24 having received the eccentric shaft portion 38 to be rotatable. Below the driving motor 30, there is provided a bearing plate 41 which allows the lower end part of the driving shaft 36 to be rotatably fitted therein and thereby supported.

Furthermore, as already mentioned above, at a predetermined position of the upper end cap 14 of the compressor casing 10, there is provided a tubular steel mount pipe 14Z which is welded thereto so as to pierce therethrough with the center axis line oriented in the vertical direction. As will be described in more detail later, there is securely provided an intake pipe 50 which passes through the mount pipe 14Z, the intake pipe 50 being adapted to draw the refrigerant gas from the refrigerant gas pipe P of the refrigerant circuit into the scroll type compression mechanism 20. Furthermore, the casing body 12 is provided hermetically with a discharge pipe 70 which discharges the refrigerant gas in the high-pressure space KK inside the compressor casing 10 out of the compressor casing 10 and which is secured to the casing body 12 so as to penetrate therethrough. The intake pipe 50 extends through the discharge space TK in the vertical direction, and the lower end part thereof is fitted into an intake portion 22K with an O-ring 60 disposed therebetween, the intake portion 22K being provided in an end plate 22A of the stationary scroll 22. Furthermore, the intake portion 22K is in communication with a hole portion 2211 that penetrates the end plate 22A in such a manner as to feed the refrigerant gas into a compression chamber 26 that is defined by a lap 22R of the stationary scroll 22 and a lap 24R of the swingable scroll 24. In this mariner, the refrigerant gas is drawn into the. compression chamber 26.

In this example, the driving motor 30 is an alternating-current motor which includes an annular stator 32 secured to the inner wall surface of the compressor casing 10 and a rotor 34 rotatably disposed inside the stator 32, with the aforementioned driving shaft 36 secured to the rotor 34. When being rotated, the driving shaft 36 causes the eccentric shaft portion 38 to be rotated, thereby driving the aforementioned swingable scroll 24, When the swingable scroll 24 is driven, the swingable scroll 24 is pivoted (swung) while being restricted from rotating around its own axis, due to the operation of a known Oldham. ring 28. The pivotal motion is produced in a circle, n with the radius being the amount of the eccentricity of the eccentric shaft: portion 38 relative to the driving shaft 36.

There is a lower space UK which is located below the driving motor 30 and kept at a high pressure, and some oil is stored in the inner bottom portion of the lower end cap 16 that defines the lower space UK. There is formed an oil feeding passage 80 as part of high-pressure oil feeding means within the driving shaft 36, and the oil feeding passage 80 is in communication with an oil chamber 80KK on the lower surface of the end plate 24A of the swingable scroll 24. The driving shaft 36 is provided with a pickup (not shown) which is linked to the lower end so as to pick up the oil stored in the inner bottom. portion of the lower end cap 16. The picked-up oil is supplied to the oil, chamber 80KK below the swingable scroll 24 through the oil feeding passage 80 in the driving shaft 36, and then. supplied from the oil chamber 80KK to each sliding portion of the scroll type compression mechanism 20 and the compression chamber 26 through a communication passage 24AR that is provided in the swingable scroll 24.

The stationary scroll 22 has the end plate 22A and the aforementioned spiral, i.e., involute lap 22R which is formed on the lower surface of the end plate 22A. On the other hand, the swingable scroll 24 has the end plate 24A and the aforementioned spiral, i.e., involute lap 24R which is formed on the upper surface of the end plate 24A, Further, the lap 22R of the stationary scroll 22 and the lap 24R of the swingable scroll 24 are opposed so as to be swingingly engaged with each other, whereby both the laps 22R and 24R form three or an appropriate number of compress. on chambers 26 between the stationary scroll 22 and the swingable scroll 24.

The driving shaft 36 located below the bearing unit 40T of the main frame 40 is provided with a balance weight 37 for maintaining dynamic balance with the swingable scroll 24 or the eccentric shaft portion 38 or the like, so that the swingable scroll 24 is pivoted without being rotated around its own axis while balance is being maintained with the balance weight 31. Further, the compression chamber 26 is configured to compress the refrigerant gas drawn in through the intake pipe 50 to a higher pressure by contracting the volume between both the laps 22R and 24R toward the center of the stationary scroll 22 as the swingable scroll 24 is pivoted.

The stationary scroll 22 is provided at the center with a discharge hole TP. The high-pressure refrigerant gas discharged from the discharge hole TP is discharged into the discharge space TK through the discharge valve 42. Then, as described above, the high-pressure refrigerant gas flows into the high-pressure space KK below the main frame 40 through the aforementioned vertical groove M which is provided. in each outer circumferential portion of the main frame 40 and the stationary scroll 22. Then, the high-pressure refrigerant gas is discharged out of the compressor casing 10 through the discharge pipe 70 provided on the casing body 12.

Now, reference will be made to FIG. 2 showing an enlarged view of the upper end cap 14 and the intake pipe 50 of the scroll type compressor described above and to FIG. 3 showing an enlarged view of the intake pipe 50. First, an iron pipe body 54 made of steel in an appropriate length and a copper pipe body 52 made of copper or another metal such as steel plated with copper in an appropriate length were prepared for the intake pipe 50. The copper pipe body 52 is less in thickness than the iron pipe body 54. The copper pipe body of this example is half or less in thickness than the iron pipe body 54. The iron pipe body 54 is provided on the lower outer circumference with an annular groove 54M along which the O-ring 60 is installed, and the lower end outer circumferential portion is formed into a tapered. guide portion 54G. The intake portion 22K provided in the end plate 22A of the stationary scroll 22 on the main body side of the scroll type compressor is formed into a guide portion with the inlet edge portion increased in diameter toward the top (upwardly), so that this guide portion and the above-mentioned guide portion 54G facilitate insertion of the intake pipe 50 into the intake portion 22K.

Furthermore, the inner periphery of a joint area 54A which is the upper end part of the iron pipe body 54 is provided with an upwardly-opened first stepped portion 54D′, into which a joint area 52A of the lower end part of the copper pipe body 52 is fitted and to which the joint area 52A is silver-brazed with a silver braze Y2. Furthermore, immediately below the first stepped portion 54D′, there is provided a second stepped portion 54D which is opened (upwardly) toward the copper pipe body 52. The inner diameter D2 of the second stepped portion 54D is equal to or less than the minimum inner diameter Di of the copper pipe body 52.

On the other hand, the outer diameter of an inlet opening edge portion FA of a basket-like filter F (the maximum outer diameter of the filter F) for removing dust mixed in the refrigerant gas is sized to be capable of passing through a region of the minimum inner diameter D1 of the copper pipe body 52 as well as being press-fitted into the second stepped portion 54D. FIG. 3 is a view showing the press-fitted filter F. The filter F of this example is formed of a mesh of thin stainless steel wire, so that the inlet opening edge portion FA is formed by a turnover of the mesh being caulked.

However, a filter F according to another embodiment is also available. For example, as the inlet opening edge portion FA, it is also acceptable to employ a stainless-steel annular plate and solder this plate to an appropriate filter body. On the other hand, to obtain the appropriate filter body, it is acceptable to solder a plurality of filter body elements divided in the circumferential direction so as to join the elements together.

As described above, the structure in which the filter F is press-fitted allows the filter F to be inserted and press-fitted into the intake pipe 50 after each part has been joined together. Thus, even in the case of the filter F provided by soldering, the problem with the solder being melted can be prevented. Furthermore, even in the case of the filter F made of a wire material reduced in diameter, the thermal damage to the wire material can be prevented. After such a filter F has been placed, the upper end part of the copper pipe body 52 is copper-brazed to the refrigerant gas pipe P.

Furthermore, even in the case of the filter F having the inlet opening edge portion FA the size of which is greater than the maximum outer diameter of the filter F of FIG. 3, the inlet opening edge portion FA can be installed by being sandwiched between the lower end bottom surface of the first stepped portion 54D′ and the lower end of the copper pipe body 52, i.e., the lower end of the joint area 52A. In this case, the inlet opening edge portion FA is preferably formed in the shape of a so-called flange that is expanded sideward, which would facilitate sandwiching of the inlet opening edge portion FA. For the installation by sandwiching, the inlet opening edge portion FA needs to be sandwiched before being silver-brazed with the silver braze Y2. Thus, the filter F requiring no soldering would be preferable.

According to the present invention, it is able to save the trouble of providing in a prescribed manner such a filter F into another pipe such as the refrigerant gas pipe P.

As another embodiment for press-fitting the opening edge portion FA of the filter F into the stepped portion, there is also available an embodiment of FIG. 4 which is different from that of FIG. 3. That is, the joint area 52A or the lower end part of the copper pipe body 52 is fitted into and silver-brazed with the silver braze Y2 to the first stepped portion 54D′ of the iron pipe body 54, in the case of which the size of the step of the first stepped portion 54D′ is greater by an appropriate size than the thickness of the joint area 52A. The filter F is press-fitted so that the opening edge portion FA is placed on the step surface that remains inward of the joint area 52A. The matters in the embodiment of FIG. 4 are the same as described in relation to the embodiment of FIG. 3 except that the opening edge portion FA is press fitted not into the second stepped portion 540 but into the first, step portion 54D′.

On the other hand, in this embodiment, the steel mount pipe 14Z is welded to the steel upper end cap 14 by arc welding as described above (the built-up portion denoted by reference number Y1). The intake pipe 50 is fitted into the mount pipe 14Z, so that the fitted portion of the copper pipe body 52 is silver-brazed with a silver braze Y3 to the mount pipe 14Z. Thus, the upper end cap assembly is formed. Since this allows the O-ring 60 to remain detached while the intake pipe 50 is being securely joined to the upper end cap 14, it is possible to prevent thermal. damage to the O-ring caused by heat. produced during the joining work. However, according to the present invention, not the aforementioned sequence of manufacture/fabrication but the following one may he employed. That is, the intake pipe 50 may be fabricated in a manner such that the lower end part thereof is fitted into the intake portion 22K provided in the end. plate 22A of the stationary scroll 22 with the O-ring 60 disposed therebetween; after that, the upper part of the intake e pipe 50 is passed through the mount pipe 14Z welded to the upper end cap 14; and then the fitted portion of the copper pipe body 52 is silver-brazed thereto with the silver braze Y3. In this case, since the copper pipe body 52 is employed, the silver brazing Y3 can be performed at a temperature lower than that for the arc welding, and thus thermal damage to the O-ring 60 can also he prevented or reduced.

Furthermore, a stepped portion 14D having a step bottom surface 14S is formed on the outer side of the peripheral lower end part of the upper end cap 14, so that the stepped portion 14D is fitted into the upper end part of the casing body 12 and then arc welded thereto (reference number Y4 of FIG. 1).

INDUSTRIAL APPLICABILITY

The present invention is applicable to the scroll type compressor.

DESCRIPTION OF REFERENCE NUMERALS

-   10 compressor casing -   12 casing body -   14 upper end cap -   14D stepped portion -   14Z mount pipe -   22 stationary scroll -   22K intake portion -   24 swingable scroll -   50 intake pipe -   52 copper pipe body -   52A joint area -   54 iron pipe body -   54A joint area -   54D stepped portion -   60 O-ring -   D1 minimum inner diameter of copper pipe body -   F filter -   FA inlet opening edge portion -   Y1, Y4 arc welded portion -   Y2, Y3 silver-brazed portion 

1. A scroll compressor in which an intake pipe for drawing in a refrigerant gas through an external pipe is securely joined to a steel compressor casing by penetrating therethrough, the compressor casing being configured to house a stationary scroll and a swingable scroll; and a lower end part of the intake pipe is fitted into an intake portion with an O-ring disposed therebetween, the intake portion being provided in the stationary scroll, the scroll compressor being characterized in that the intake pipe is configured to have a steel iron pipe body on the intake portion side and a copper pipe body joined to an upper end part of the iron pipe body, the copper pipe body being made of copper or another metal a surface of which is plated with copper; the copper pipe body of the intake pipe is silver-brazed to the compressor casing; and a filter for removing dust mixed in the refrigerant gas is installed in the intake pipe.
 2. A scroll compressor in which an intake pipe for drawing in a refrigerant gas through an external pipe is securely joined to a steel compressor casing by penetrating therethrough, the compressor casing being configured to house a stationary scroll and a swingable scroll; and a lower end part of the intake pipe is fitted into an intake portion with an O-ring disposed therebetween, the intake portion being provided in the stationary scroll, the scroll compressor being characterized in that the intake pipe is configured to have a steel iron pipe body on the intake portion side and a copper pipe body joined to an upper end part of the iron pipe body, the copper pipe body being made of copper or another metal a surface of which is plated with copper; the copper pipe body of the intake pipe is silver-brazed to the compressor casing; a stepped portion which has an inner diameter equal to or less than the minimum inner diameter of the copper pipe body and which is opened toward the copper pipe body is provided inside the iron pipe body; and an opening edge portion of a filter for removing dust mixed in the refrigerant gas has an outer diameter which allows for passing through a region of the minimum inner diameter, with the opening edge portion of the filter press-fitted into the stepped portion.
 3. The scroll compressor according to claim 1, wherein the filter is formed by soldering.
 4. The scroll compressor according to claim 2, wherein the filter is a mesh of thin metal wire, and the opening edge portion is formed by securely caulking a region into which the opening edge portion of the body of the filter is outwardly turned over.
 5. A scroll compressor in which an intake pipe for drawing in a refrigerant gas through an external pipe is securely joined to a steel compressor casing by penetrating therethrough, the compressor casing being configured to house a stationary scroll and a swingable scroll; and a lower end part of the intake pipe is fitted into an intake portion with an O-ring disposed therebetween, the intake portion being provided in the stationary scroll, the scroll compressor being characterized in that the intake pipe is configured to have a steel iron pipe body on the intake portion side and a copper pipe body joined to the upper end part of the iron pipe body, the copper pipe body being made of copper or another metal the surface of which is plated with copper; the copper pipe body of the intake pipe is silver-brazed to the compressor casing; and an opening edge portion of a filter for removing dust mixed in the refrigerant gas is sandwiched between the iron pipe body and the copper pipe body in a joint area thereof
 6. The scroll compressor according to claim 2, wherein the filter is formed by soldering. 